Comparison of essential oil content and composition of four accessions of Satureja macrantha C. A. Mey. in three years after cultivation in climatic condition of Tehran

The genus Satureja belongs to the Lamiaceae family. Satureja macrantha C. A. Mey. is an aromatic plant growing wild in Zanjan، Kordestan، Hamedan، and Kermanshah provinces. In this research، to domesticate this species and study its essential oil content and composition، the seeds of four accessions were collected from natural habitats and cultivated in the research farm of Research Institute of Forests and Rangelands. The experiment was conducted in a randomized complete blocks design with three replications. To compare the essential oil yields and constituents، the aerial parts of each accession were collected in full flowering stage in three consecutive years. After drying in room temperature، the plant materials were subjected to hydro-distillation. The oil yields were calculated and the oil compositions were identified by GC and GC/MS analysis and retention indices. Results showed that the major compounds in all oils were recorded to be thymol، p-cymene and g-terpinene with different percentages. However، carvacrol was also detected in the oils whose value was not considerable. In addition، the oil yields increased gradually with plant growth in all accessions. The quality of oils was also improved with plant aging، except for one accession، so that three- year old plants contained more oil and more phenolic compounds، thymol and carvacrol as compared to one-year old plants. The elimination and appearance of some minor components in the oils with plant aging showed that oil analysis at the first year of cultivation of an aromatic plant did not produce acceptable results. Therefore، to obtain reliable results، the oils should be studied in a few consecutive years.